Re: ppc64le reliable stack unwinder and scheduled tasks

On 1/14/19 12:09 PM, Josh Poimboeuf wrote:

On Mon, Jan 14, 2019 at 11:46:59AM -0500, Joe Lawrence wrote:

quoted

@@ -158,11 +158,21 @@ save_stack_trace_tsk_reliable(struct task_struct *tsk,
  			return 1; /* invalid backlink, too far up. */
  		}
  
+		/* We can only trust the bottom frame's backlink, the rest
+		 * of the frame may be uninitialized, continue to the next. */
+		if (firstframe--)
+			goto next;

Won't this decrement firstframe on every iteration, so when firstframe
is 0, it will decrement it to -1, causing it to 'goto next' on all
future iterations?

Argg, yes, that should be:

if (!firstframe) {
	firstframe = 0;
	goto next;
}

Apologies for the monday-morning crap-patch.

/runsoff to find some more caffeine

-- Joe